Plugin:check log
! /bin/sh # # Log file pattern detector plugin for Nagios # Written by Ethan Galstad (nagios@nagios.org) # Last Modified: 07-31-1999 # # Usage: ./check_log # # Description: # # This plugin will scan a log file (specified by the option) # for a specific pattern (specified by the option). Successive # calls to the plugin script will only report *new* pattern matches in the # log file, since an copy of the log file from the previous run is saved # to . # # Output: # # On the first run of the plugin, it will return an OK state with a message # of "Log check data initialized". On successive runs, it will return an OK # state if *no* pattern matches have been found in the *difference* between the # log file and the older copy of the log file. If the plugin detects any # pattern matches in the log diff, it will return a CRITICAL state and print # out a message is the following format: "(x) last_match", where "x" is the # total number of pattern matches found in the file and "last_match" is the # last entry in the log file which matches the pattern. # # Notes: # # If you use this plugin make sure to keep the following in mind: # # 1. The "max_attempts" value for the service should be 1, as this # will prevent Nagios from retrying the service check (the # next time the check is run it will not produce the same results). # # 2. The "notify_recovery" value for the service should be 0, so that # Nagios does not notify you of "recoveries" for the check. Since # pattern matches in the log file will only be reported once and not # the next time, there will always be "recoveries" for the service, even # though recoveries really don't apply to this type of check. # # 3. You *must* supply a different for each service that # you define to use this plugin script - even if the different services # check the same for pattern matches. This is necessary # because of the way the script operates. # # Examples: # # Check for login failures in the syslog... # # check_log /var/log/messages ./check_log.badlogins.old "LOGIN FAILURE" # # Check for port scan alerts generated by Psionic's PortSentry software... # # check_log /var/log/message ./check_log.portscan.old "attackalert" # # Paths to commands used in this script. These # may have to be modified to match your system setup. # TV: removed PATH restriction. Need to think more about what this means overall #PATH="" ECHO="/bin/echo" GREP="/bin/egrep" DIFF="/usr/bin/diff" TAIL="/usr/bin/tail" CAT="/bin/cat" RM="/bin/rm" CHMOD="/bin/chmod" TOUCH="/bin/touch" PROGNAME=`/bin/basename $0` PROGPATH=`echo $0 | sed -e 's,\\/^\\/^\\/*$,,'` REVISION="1.4.16" . $PROGPATH/utils.sh print_usage() { echo "Usage: $PROGNAME -F logfile -O oldlog -q query" echo "Usage: $PROGNAME --help" echo "Usage: $PROGNAME --version" } print_help() { print_revision $PROGNAME $REVISION echo "" print_usage echo "" echo "Log file pattern detector plugin for Nagios" echo "" support } # Make sure the correct number of command line # arguments have been supplied if [ $# -lt 1 ]; then print_usage exit $STATE_UNKNOWN fi # Grab the command line arguments #logfile=$1 #oldlog=$2 #query=$3 exitstatus=$STATE_WARNING #default while test -n "$1"; do case "$1" in --help) print_help exit $STATE_OK ;; -h) print_help exit $STATE_OK ;; --version) print_revision $PROGNAME $REVISION exit $STATE_OK ;; -V) print_revision $PROGNAME $REVISION exit $STATE_OK ;; --filename) logfile=$2 shift ;; -F) logfile=$2 shift ;; --oldlog) oldlog=$2 shift ;; -O) oldlog=$2 shift ;; --query) query=$2 shift ;; -q) query=$2 shift ;; -x) exitstatus=$2 shift ;; --exitstatus) exitstatus=$2 shift ;; *) echo "Unknown argument: $1" print_usage exit $STATE_UNKNOWN ;; esac shift done # If the source log file doesn't exist, exit if [ ! -e $logfile ]; then $ECHO "Log check error: Log file $logfile does not exist!\n" exit $STATE_UNKNOWN elif [ ! -r $logfile ] ; then $ECHO "Log check error: Log file $logfile is not readable!\n" exit $STATE_UNKNOWN fi # If the old log file doesn't exist, this must be the first time # we're running this test, so copy the original log file over to # the old diff file and exit if [ ! -e $oldlog ]; then $CAT $logfile > $oldlog $ECHO "Log check data initialized...\n" exit $STATE_OK fi # The old log file exists, so compare it to the original log now # The temporary file that the script should use while # processing the log file. if [ -x /bin/mktemp ]; then tempdiff=`/bin/mktemp /tmp/check_log.XXXXXXXXXX` else tempdiff=`/bin/date '+%H%M%S'` tempdiff="/tmp/check_log.${tempdiff}" $TOUCH $tempdiff $CHMOD 600 $tempdiff fi $DIFF $logfile $oldlog | $GREP -v "^>" > $tempdiff # Count the number of matching log entries we have count=`$GREP -c "$query" $tempdiff` # Get the last matching entry in the diff file lastentry=`$GREP "$query" $tempdiff | $TAIL -1` $RM -f $tempdiff $CAT $logfile > $oldlog if [ "$count" = "0" ]; then # no matches, exit with no error $ECHO "Log check ok - 0 pattern matches found\n" exitstatus=$STATE_OK else # Print total matche count and the last entry we found $ECHO "($count) $lastentry" exitstatus=$STATE_CRITICAL fi exit $exitstatus Category:Plugin